故障现象屏幕左上角处有黑色暗区分析检修根据故障现象，首先应判断黑色暗区是否因场消隐回路不良引起。断开场消隐回路，若出现屏幕上有暗角，且色纯正常，则可判定暗角是因显像管或偏转线圈自身故障所致；若屏幕上有暗角，但色纯不良，则说明暗角是因色纯调节不良所致。电路 Fault phenomenon screen at the upper left corner of the black dark area analysis and repair According to the fault phenomenon, first of all should judge whether the black dark area caused by bad field blanking circuit. Open the field blanking circuit, if there is vignetting on the screen, and the pure color normal, you can determine the dark corner is due to tube or deflection coil itself caused by failure; if the screen with vignetting, but pure color, then Vignetting is due to poor color adjustment. Circuit